This invention relates to the field of beach-front erosion prevention systems, and more particularly, to a sand dune and shore-line erosion prevention system.
The problem of beach-front, and more specifically, sand dune erosion has plagued beaches and costal regions around the world for hundreds of years. However, this natural phenomena appears to have gotten worse in recent years, especially in certain regions of the United States, due to increasingly more violent weather conditions. In order to secure beach-front ecosystems around the world, and thereby helping to minimize the damage to personal, business and governmental properties caused by severe high tides and storms, the subject invention is directed to a sand dune and shore-line erosion prevention system which will solve the problem of the deterioration and erosion of beach-fronts, and more particularly, the sand dunes and shore lines of these beach-front ecosystems.
Older existing systems in this field were bulk heads (consisting of creosote piling and wood walls, corrugated steel, CCA retaining walls or solid concrete walls with reinforced steel), rock jetties and revetments. These systems lacked longevity, and would eventually break apart, rot and/or deteriorate due to the materials used, as well as the essential physical principle behind the construction of these systems. In particular, these prior art systems were usually hardened structures erected in such a manner that all forces of the approaching waves, whether storm related or not, were directly opposed (met head-on) by the structure, instead of the structure working with the force of the wave. Additionally, these prior art structures allowed the sand from the beaches and dunes to be swept away as the waves retreated back to the sea. This sand removal left the structures exposed to all weather elements, causing erosion of the structures, which eroded material ended up being deposited onto the beaches, and eventually was swept into the sea.
Newer prior art erosion prevention systems generally related to the subject field can be seen in such U.S. patents as the patents to Ianell, U.S. Pat. No. 5,104,258, Rauch, U.S. Pat. Nos. 5,120,156 and 4,818,141, Schaaf et. al., U.S. Pat. No. 4,711,598, Creter and Creter, Jr. et. al., U.S. Pat. Nos. 5,238,326, 5,102,257, 4,913,595 and 4,502,816, and Sample, U.S. Pat. No. 4,966,491, among others. Some of these prior art systems are directed to structures which work with the force of the wave in order to dissipate the wave force, and thereby help prevent erosion of sand dunes and shore-lines. Others of these systems are reef-like structures which remain in the water in order to either collapse the wave prior to its reaching the shore-line and/or to help collect sand removed from the shore-line by the undertow force of the wave.
Although all of these prior art erosion prevention systems have their own unique benefits, none of them completely solve the problem of sand dune erosion due to high velocity storm waves, nor do any of them fully prevent the retreat of sand from a beach-front shore-line due to undertow forces. Accordingly, it would be desirable to have a system which, on the one hand, fully prevents sand dune erosion due to any type of wave force, whether storm force or normal force, and can also prevent retreat of sand back to the water due to undertow forces. It would also be desirable that such a system be constructed of materials which are ecologically undamaging to the beach-front ecosystem.